My water's cloudy and my shrimp are dying, but I have perfect params. Any idea of what my issue could be?

Sorry for the question. I'll probably be cross posting this everywhere for more opinions. I have a one-gallon walstead jarrarium. It's heavily planted and has been running smoothly for four-ish months with a stock of six RCS and a couple of snails that snuck in. Perfectly clear water, everybody was happy.

A couple of days ago I did a big trim and fed my shrimp some broiled cucumber. These were the only things that I did out of the ordinary. Since then, my water has become murky and grey, and I've found two of my shrimp dead. The snails have been hanging out on the top of the water like I've seen them do if there is too much ammonia in the water, but all my params are fine.

I did an emergency water change last night, and everybody looked much happier. Shrimp moved more, snails left the water line etc. But this morning I woke up and it's again quite cloudy and snails are at the top. Again, perfect params. What could be going on? I'm stumped!